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How to catch integer(0)?

.... True, but I don't think there's much of a performance issue either way, and length(x) == 0L reads more clearly to me. – Richie Cotton Jun 24 '11 at 10:04 ...
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Display open transactions in MySQL

... How can I display these open transactions and commit or cancel them? There is no open transaction, MySQL will rollback the transaction upon disconnect. You cannot commit the transaction (IFAIK). You display threads using SHOW FULL PROCESSLIST See: http:/...
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Can C++ code be valid in both C++03 and C++11 but do different things?

Is it possible for C++ code to conform to both the C++03 standard and the C++11 standard, but do different things depending on under which standard it is being compiled? ...
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How does zip(*[iter(s)]*n) work in Python?

...unction call. Therefore you're passing the same iterator 3 times to zip(), and it pulls an item from the iterator each time. x = iter([1,2,3,4,5,6,7,8,9]) print zip(x, x, x) share | improve this a...
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@Media min-width & max-width

...ult CSS for the older browsers, as older browsers including i.e. 5.5, 6, 7 and 8. Can't read @media. When I use @media I use it like this: <style type="text/css"> /* default styles here for older browsers. I tend to go for a 600px - 960px width max but using percentages */ ...
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How to select a single field for all documents in a MongoDB collection?

... MongoDB, I have a student collection with 10 records having fields name and roll . One record of this collection is: 1...
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Ruby 2.0.0p0 IRB warning: “DL is deprecated, please use Fiddle”

...alled my older versions of Ruby, removed all of my gems (including Rails), and installed Ruby 2.0. In other words, a totally clean re-install. Upon starting IRB, I received this message: ...
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Set time part of DateTime in ruby

Say I have a datetime object eg DateTime.now . I want to set hours and minutes to 0 (midnight). How can I do that? 4 Ans...
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Or versus OrElse

What's the difference between or and OrElse ? 8 Answers 8 ...
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Rotating and spacing axis labels in ggplot2

... In the newest version of ggplot2 the command would be: q + theme(axis.text.x=element_text(angle = -90, hjust = 0)) – rnorberg Sep 28 '12 at 13:18 ...